1. Field of the Invention
The present invention relates to an advance and retreat assist tool for an endoscopic treatment instrument.
2. Description of the Related Art
For example, Jpn. Pat. Appln. KOKAI Publication No. 11-225950, Jpn. Pat. Appln. KOKAI Publication No. 2007-159756, Jpn. Pat. Appln. KOKAI Publication No. 2010-57919, and Jpn. Pat. Appln. KOKAI Publication No. 9-276211 have each disclosed an advance and retreat assist tool for an endoscopic treatment instrument which assists a treatment instrument of an endoscope in advancing and retreating.
For example, in Jpn. Pat. Appln. KOKAI Publication No. 11-225950, Jpn. Pat. Appln. KOKAI Publication No. 2007-159756, Jpn. Pat. Appln. KOKAI Publication No. 2010-57919, and Jpn. Pat. Appln. KOKAI Publication No. 9-276211, the advance and retreat assist tool is attached to a treatment instrument insertion hole portion so that the advance and retreat assist tool is provided straight along the central axis direction of the treatment instrument insertion hole portion provided in a treatment instrument insertion portion. The central axis direction of the treatment instrument insertion hole portion is slanted relative to the central axis direction of a grasping portion. Thus, the advance and retreat assist tool is slanted relative to the central axis direction of the grasping portion.